This invention relates to a method for making walls for buildings, particularly walls of concrete or similar material made using forms to shape the wall.
A common method of building walls for houses and other buildings is to prepare forms outlining the shape of the wall, pour concrete or other curable material into the form, and then allow the material to harden to complete the wall. The forms are often plywood, particle board or other wood product, steel or aluminum and are usually removed when the wall is completed. Often, the forms cannot be reused and must be disposed of or consumed in some other, lower value application. In addition, assembling and dissembling the forms is labor-intensive and time-consuming.
A wall made by the foregoing method often must be insulated. This is particularly true if the wall is abovegrade, but is also true in many areas for below-grade construction. An example of the latter is a home basement that may be used as habitable space, or a basement in a home or office building in which thermal insulation not only provides comfort but also helps reduce structural damage that is created by temperature cycling. In the method described above, insulation is added as a separate construction step. In addition, the insulation can be installed only at the external surfaces of the wall. A common method of doing this is to construct a series of studs on the inside of the wall, place insulation in the space created between the studs, and then cover the studs with a material such as drywall or plaster to form an inside wall surface.
For aesthetic and comfort reasons, it is often desirable to cover the exposed surfaces of the wall. When the wall is made in the manner described above, this is accomplished in subsequent operations. Drywalling or plastering, as described in the previous paragraph, are examples of this. In the case of an exterior wall, a facade such as brick, siding, stucco or the like is often attached.
It has been proposed to build concrete walls using plastic forms. Among such proposals is that described in U.S. Pat. Nos. 5,706,620, 5,729,944 and WO publication nos. 97/32092, 97/32095, 94/18405, 94/21867 and 95/33106, all to De Zen. De Zen describes a wall construction based on interlocking, prefabricated plastic sectional forms of roughly rectangular cross-section. A series of these forms are connected to make a form for a wall, and then filled with concrete to complete the wall. The forms may be adapted so that they contain a layer of insulating foam on the interior or exterior surface, as shown for example in WO publication nos. 97/32092 and 97/32095. Because of the design of the forms, the insulating foam is generally restricted to a pour-in-place type, which tends to undergo dimensional changes as it ages. As a result of these dimensional changes, the integrity of the insulating layer is sometimes lost. Even more significantly, the insulating layer often distorts the plastic form itself. This distortion can interfere with the ability of adjacent forms to interlock easily. Yet another problem is that the forms are often bulky because they have rectangular cross-sections.
It would be desirable to provide an inexpensive, easily assembled form for making walls of concrete and other loadbearing materials. Preferably, such a form is easily adaptable to a variety of wall sizes and shapes and allows for the easy installation of services and openings. It would further be desirable to provide a method for making a wall in which the wall could be built and insulated in a single step, and preferably in which aesthetically and functionally pleasing interior and/or exterior surfaces could be provided as well.